diff --git a/app/models/exercise.rb b/app/models/exercise.rb
new file mode 100644
index 000000000..752441947
--- /dev/null
+++ b/app/models/exercise.rb
@@ -0,0 +1,7 @@
+class Exercise < ActiveRecord::Base
+  include Redmine::SafeAttributes
+  belongs_to :user
+  has_many :exercise_questions, :dependent => :destroy,:order => "#{ExerciseQuestion.table_name}.question_number"
+  has_many :exercise_users, :dependent => :destroy
+  has_many :users, :through => :exercise_users #该文件被哪些用户提交答案过
+end
diff --git a/app/models/exercise_answer.rb b/app/models/exercise_answer.rb
new file mode 100644
index 000000000..14b60982a
--- /dev/null
+++ b/app/models/exercise_answer.rb
@@ -0,0 +1,8 @@
+class ExerciseAnswer < ActiveRecord::Base
+  #学生答题
+  include Redmine::SafeAttributes
+
+  belongs_to :user
+  belongs_to :exercise_question
+  belongs_to :exercise_choices
+end
diff --git a/app/models/exercise_choices.rb b/app/models/exercise_choices.rb
new file mode 100644
index 000000000..8e67a8c0a
--- /dev/null
+++ b/app/models/exercise_choices.rb
@@ -0,0 +1,7 @@
+class ExerciseChoices < ActiveRecord::Base
+  include Redmine::SafeAttributes
+
+  belongs_to :exercise_question
+  has_many :exercise_answers, :dependent => :destroy
+  has_many :exercise_standard_answers, :dependent => :destroy
+end
diff --git a/app/models/exercise_question.rb b/app/models/exercise_question.rb
new file mode 100644
index 000000000..64ec53e4c
--- /dev/null
+++ b/app/models/exercise_question.rb
@@ -0,0 +1,8 @@
+class ExerciseQuestion < ActiveRecord::Base
+  include Redmine::SafeAttributes
+
+  belongs_to :exercise
+  has_many :exercise_choiceses, :order => "#{ExerciseChoices.table_name}.choice_position",:dependent => :destroy
+  has_many :exercise_answers, :dependent => :destroy
+  has_many :exercise_standard_answers, :dependent => :destroy
+end
diff --git a/app/models/exercise_standard_answer.rb b/app/models/exercise_standard_answer.rb
new file mode 100644
index 000000000..2b67a83a2
--- /dev/null
+++ b/app/models/exercise_standard_answer.rb
@@ -0,0 +1,7 @@
+class ExerciseStandardAnswer < ActiveRecord::Base
+  #标准答案
+  include Redmine::SafeAttributes
+
+  belongs_to :exercise_question
+  belongs_to :exercise_choices
+end
diff --git a/app/models/exercise_user.rb b/app/models/exercise_user.rb
new file mode 100644
index 000000000..2d5da5d95
--- /dev/null
+++ b/app/models/exercise_user.rb
@@ -0,0 +1,6 @@
+class ExerciseUser < ActiveRecord::Base
+  include Redmine::SafeAttributes
+
+  belongs_to :user
+  belongs_to :exercise
+end
diff --git a/app/models/user.rb b/app/models/user.rb
index edc29c015..9e470380d 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -81,6 +81,12 @@ class User < Principal
   has_many :poll, :dependent => :destroy #用户创建的问卷
   has_many :answers, :source => :poll, :through => :poll_users, :dependent => :destroy #用户已经完成问答的问卷
   # end
+  #在线测验相关关系
+  has_many :exercise_users, :dependent => :destroy  #答卷中间表
+  has_many :exercise_answers, :dependent => :destroy  #针对每个题目学生的答案
+  has_many :exercises, :dependent => :destroy  #创建的试卷
+  has_many :exercises_answers, :source => :exercises, :through => :exercise_users, :dependent => :destroy #用户已经完成问答的试卷
+  #end
   #作业相关关系
   has_many :homework_commons, :dependent => :destroy
   has_many :student_works, :dependent => :destroy
diff --git a/db/migrate/20151113025341_exercise.rb b/db/migrate/20151113025341_exercise.rb
index 8fdcf0a9e..696f8d953 100644
--- a/db/migrate/20151113025341_exercise.rb
+++ b/db/migrate/20151113025341_exercise.rb
@@ -6,8 +6,7 @@ class Exercise < ActiveRecord::Migration
       t.integer :course_id
       t.integer :exercise_status
       t.integer :user_id
-      t.datetime :start_at
-      t.datetime :end_at
+      t.integer :time
       t.timestamps
     end
   end
diff --git a/db/migrate/20151113025459_exercise_question.rb b/db/migrate/20151113025459_exercise_question.rb
index 3ab084f13..5e83504c5 100644
--- a/db/migrate/20151113025459_exercise_question.rb
+++ b/db/migrate/20151113025459_exercise_question.rb
@@ -3,6 +3,7 @@ class ExerciseQuestion < ActiveRecord::Migration
     create_table :exercise_question do |t|
       t.string :question_title
       t.integer :question_type
+      t.integer :question_number
       t.integer :exercise_id
       t.timestamps
     end
diff --git a/db/migrate/20151113025751_user_exercise.rb b/db/migrate/20151113025751_user_exercise.rb
index b0a003d1d..a49053146 100644
--- a/db/migrate/20151113025751_user_exercise.rb
+++ b/db/migrate/20151113025751_user_exercise.rb
@@ -1,14 +1,15 @@
 class UserExercise < ActiveRecord::Migration
   def up
-    create_table :user_exercise do |t|
+    create_table :exercise_user do |t|
       t.integer :user_id
       t.integer :exercise_id
       t.integer :score
+      t.datetime :start_at
       t.timestamps
     end
   end
 
   def down
-    drop_table :user_exercise
+    drop_table :exercise_user
   end
 end